This makes a delicate sponge that separates in the oven so there's a layer of lemon pudding in the bottom of the bowl. We like raspberry sorbet on top for color and brightness, but my restaurant partner Rich Melman likes my Buttermilk Ice Cream on top for a creamier soothing experience.
Preheat the oven to 325 degrees F. Butter the ramekins.
In a mixer with a paddle attachment, cream the butter with 1/3 cup of the sugar. Mix in the egg yolks; then fold in the flour (it may look curdled.) With a whisk, work in the milk, lemon juice and lemon zest.
In a standing mixer fitted with a whisk attachment, whip the egg whites until foamy. Gradually add the 3/4 cup sugar and continue whipping on medium speed until glossy. Whisk 1/4 of the whites into the lemon mixture and then fold in the remainder.
Portion the batter immediately into the buttered dishes filling 3/4 of the way full and bake immediately in a water bath covered with foil for 30 minutes. Serve warm topped with a scoop of raspberry sorbet.